1. Technical Field
The present disclosure relates to a backlight adjusting system and a backlight adjusting method, and more particularly to a backlight adjusting system and a backlight adjusting method for adjusting backlight brightness of a light emitting element for a display panel based on an ambient light around the display panel.
2. Description of Related Art
Display quality of a liquid crystal display (LCD) is affected by an ambient light around the LCD. In the LCD, a backlight adjusting system is used to adjust a backlight brightness of a light emitting element for an LCD panel based on the ambient light. Typically, the backlight brightness is adjusted to increase when the ambient brightness of the ambient light is high, and is adjusted to decrease when the ambient brightness is low, so that the display quality can be improved.
Referring to FIG. 1, a conventional backlight adjusting system 1 includes a brightness sensor 11, an analog-to-digital converter 12, a storage media 13, a processor 14 and a driver 15. The brightness sensor 11 is configured to detect ambient brightness and to generate an actual ambient brightness signal accordingly. The analog-to-digital converter 12 is coupled to the brightness sensor 11 and configured to convert the actual ambient brightness signal to an actual ambient brightness value in an analog-to-digital manner. The storage media 13 is configured to store a look-up table which includes a list of predetermined ambient brightness values and a list of predetermined pulse duty values corresponding respectively to the predetermined ambient brightness values. The processor 14 is electrically coupled to the analog-to-digital converter 12 and the storage media 13, and configured to obtain a target pulse duty value from the predetermined pulse duty values by matching the actual ambient brightness value with one of the predetermined ambient brightness values. The driver 15 is electrically coupled to the processor 14, and configured to generate a driving signal based on the target pulse duty value utilizing pulse width modulation techniques for driving the light emitting element so as to adjust the backlight brightness.
The aforesaid backlight adjusting system 1 has some problems. Although the backlight brightness can be adjusted through the look-up table to improve the display quality, the backlight brightness thus obtained is unlikely to achieve an optimal condition, hence, an optimal display quality is also unlikely to be achieved. Furthermore, since the backlight brightness is determined by the use of the aforementioned look-up table, it cannot be adjusted with the variations of the brightness caused by the aging of the light emitting element or by the use of different light emitting elements having different illuminating characteristics.